Systems and methods that employ 3D sonar on an underwater vehicle to conduct inspections of subsea and other underwater structures is known from WO 2012/061069, WO 2012/061097, WO 2012/061099, WO 2012/061137, WO 2012/061135, and WO 2012/061134, each of which is incorporated herein by reference in their entirety. In WO 2012/061134 and WO 2012/061135, data resulting from the 3D sonar is used to obtain information about the position and orientation of the underwater vehicle relative to the underwater structure or about whether a structural change to the underwater structure has occurred.